Stroke Active Learning Flashcards
What is a stroke?
a sudden onset focal CNS deficit due to vascular cause
WHat is a TIA?
It’s a TRANSIENT neurologic dysfunction without evidence for cerebral infarct
it’s caused by focal brain, spinal cord, or retinal ischemia wihtout acute infarction
NO PERMANENT TISSUE DAMAGE
What is the difference between a TIA and a TSI?
A TSI is transient symptoms with infarction
So patients have symptoms that totally resolve, but they have a lesion on MRI - so basically a damaging stroke with no permanent effects
What are the two types of stroke? Which is more common?
hemorrhagic and ischemic (most common)
What are the vast majority of strokes caused by in the US?
atherosclerotic disease
What happens in an ischemic stroke?
a direct thrombosis or embolism from another source occludes a cerebral vessel, cutting off oxygen supply to the regions supplied by the vessel, leading to neuronal death and neurological deficit
How long does it take for neurons to start dying after osygen is cut off?
only 4 minutes
What are some other causes of ischemic stroke besides atheroscleotic disease? In what group are these most common?
vasculitis, sickle cell crisis, severe preeclampsia, vertebral or carotid artery dissection, complicated migraine with vasospasm, sympathomimetic induced vasospasm from drug use like cocaine or amphetamines
adults younger then 45 years of age
How can ischemic strokes be further classified?
large vessel or small vessel
What vessels are most often affected in anterior circulation? Posterior circulation?
anterior: 1. common carotid 2. MCA 3. ACA
posterior: 1. vertebral artery 2. basilar artery 3. PCA
What vessels are affected in smal vessel ischemic stroke and what’s the term for these strokes?
the penetrating arteries
called lacunar stroke
What past medical history factor is very much associated with lacunar stroke?
HTN
it induces endotheliual damage, such that the penetrating arteries have an increased risk of bleeding and clot formation
What is the difference between intracerebral stroke and subarachnoid hemorrhage morphologically?
intracerebral stroke is bleeding into the brain itself
subarachnoid hemorrhage is bleeding into the space between the arachnoid and the pia
How do intracerebral stroke and subarachnoid hemorrhage differ symptomatically?
intracerebral stroke involves sudden focal neurological deficits but no real headache
Subarachnoid hemorrhage includes thunderclap headache, LOC, focal neuro findings, nausea, vomiting, photophobia, nuchal rigidity, etc.
What percentage of strokes are intracerebral hemorrhage?
13%
What are the risk factors for intracerebral hemorrhage?
increasing age
male
HTN
EtOH
tobacco
diabetes
How do you diagnose a hemorrhagic stroke?
head CT
What is the current management for intracranial hemorrhage?
- STOP or reverse anticoagulants if they’r eon them
- surgical removal of clots may improve outcomes
- lowering BP maybe contribute to improved fucntion in survivors
What are subarachnoid hemorrhages usually caused by?
trauma and shear forces that tear the perforating vessels feeding the underlying ocrtex
more common in elderly because their brains have shrunk a bit
What is the most common NON-TRAUMATIC cause of subarachnoid hemorrhage?
ruptured berry aneurysm
What are the demographics of berry aneurysm rupture?
mean age 55
50% mroe common in men
blacks twice as often as whites
What is a symptom that can warn of a berry aneurysm?
sentinel headaches - during exercise or sex
If a head CT is inconclusive but you have high suscpicion for a subarachnoid hemorrhage, what other diagnostic test can you do?
do an LP and look for blood in the CSF
What drug can you give for SAH management?
Nimodipine
it’s a Ca2+ channel blocker that preferentially affects the CNS
we think it works to dilate small vessels to increase collateral circulation and preserve cerebral perfusion in the event of massive bleeding
What are the surgical options for a berry aneurysm that hasn’t ruptured yet?
clipping or endovascular coiling
both have risk though, so you can consider watching a patient with serial imaging to see any growth or change in the aneurysm
True or false, SAH is associated with recurrent headaches or recent use of NSAIDs
false
In general, what to strokes of the anterior circulation cause?
contralateral weakness and sensory deficits
What symptoms will result from an MCA stroke?
- motor and sensory deficits in the face and arms
- a homonymous hemianopsia with ipsilateral gaze deviation (looking at their lesion)
Strokes of the dominant cerebral hemisphere will produce what? How about the nondominant?
dominant = usually left = aphasia
nondominant = usually right = contralateral hemineglect
What will the symptoms of an anterior cerebral artery stroke be?
- motor and sensory loss in the contralateral leg
- personality changes and other frontal lobe issues
- blindness in the ipsilateral eye (since opghlamic artery comes off the ACA)
What will you get in stroke of the vertebral artery?
you get cerebellar dysfunction, with symptoms of vertigo, blurred vision, vomiting, nystagmus, ataxia, and postural isntability
also lateral medullary infarct with numbness on the right side of the face, but left side of the body
What’s another name for the lateral medullary infarct causing cross sensory symptoms?
Wallenberg syndrome
What symptoms will you see wiht a basilar artery stroke?
cranial nerve palsies
What are the mortality rates for basilar artery stroke?
really bad - 90% die
What symptoms will a patient have in a posterior cerebral artery stroke?
visual problems - contralateral field loss with macular sparing
Where will a stroke be if you have pure motor symptoms? Pure sensory symptoms?
(note that these are lacunar strokes)
motor = internal capsule
sensory - thalamus
Why is asking about when a patient was last seen normal so important?
because if they first began experiencing symptoms less than 4/5 horus ago, they may be candicates for TPN (Fibrinolytic therapy)
Why should you do a rectal exam i fyou’re thinking about giving TPN?
TPN will make you bleed, so if you already have a GI bleed, that would be bad news
What are some other labs and tests you might do for someon who presents with potential stroke?
CB, BPM. Hepatic progiel, lipid profile, INR
EKG, Telemetry, Carotid doppler, echocardiogram
How soon should patients start taking aspirin after experiencing an ischemic stroke or TIA?
witin 24 to 48 hours, but not before
What drug can be used in an aspirin allergy?
clopidogrel
What should you do with someone’s blood pressure immediatley after a stroke?
it will probably be high and you should leave it there!
The higher pressure will mean the brain regions that have been cut off will be perfused
If someone has a stroke associated with moderate to severe carotid artery disease, what prodecure iwll reduce the risk or recurrent stroke?
carotid endarterectomy
What drugs will you initiate for someone diagnosed with Afib?
anticoagulants - afib causes the blood to pool and more likely to clot
